This invention relates to signs and indicators that have raised surfaces to permit reading by the blind.
Raised letter signage has become increasingly employed in order to assist persons who are visually impaired. Besides having normal alphabetic letters that are raised, such signs may also include information written in Braille.
When a sign has Braille lettering, a person who is blind must tactically search over the surface of the sign to locate the Braille lettering. This is time consuming and frustrating.
It is known to provide a key locator at a standard position on a sign carrying Braille which serves to guide a blind person in locating the Braille text. An example is a notch formed in the periphery of the sign along its left, vertical edge. The Braille text may then be positioned horizontally to the right of the notch, and is thereby readily locatable. A reference to prior art; U.K. Patent Application GB 2 263 354A addresses a similar objective.
It is known to produce raised-surface signage by a lamination procedure that provides a sign composed of multiple layers. These layers may be of differing colours, enhancing the ease with which sighted persons may see the lettering on the sign. Examples of patents addressing this technology are U.S. Pat. Nos. 5,246,757, 5,346,571 and 5,389,413 to R. R. Condon et al.
The lamination techniques of the foregoing patents produce 3-D sign face constructions comprising in sequence:
(a) a conformed laminate comprising in sequence:
(1) a sign face layer, wherein the sign face layer is a semi-rigid or rigid conformable thermoplastic sheeting;
(2) a first adhesive layer;
(3) one or more foreground visual characters, wherein the visual characters are cut from a cuttable conformable material having a thickness in the range of 1-5 mils;
(4) a second adhesive layer;
(5) a background colour layer, wherein the background colour layer is conformable material;
(6) a third adhesive layer;
(b) one or more 3-D characters positioned in register with the visual characters, wherein the 3-D characters are cut from a cuttable material having a thickness in the range of 10-50 mils;
(c) raised braille characters that protrude above the normal surface of the sign face layer.
Further, a substrate layer in the form of a rigid backing such as plastic may, in practice underlie the 3-D layer and extend to the edge of the sign.
The adhesive layers in the prior patent reference need not be physically separated from the cuttable, conformable material or the 3-D cuttable material during assembly. These materials may be manufactured so that they carry a self-adhesive coating, like a peel and stick label.
In the past it has been customary to cut a reference notch as a Braille locator in the edge of such a sign in a manner that removes a portion of the background colour layer and substrate, if present. This results in a sign wherein the reference notch is clearly visible against environmental background surfaces that are typically of a colour which contrasts with the background colour layer of the sign. This is aesthetically unattractive. Usually the background colour of the sign does contrast with the environmental background surface because a good contrast enables low-vision persons to locate the sign easily and this feature is usually required by specifiers and customers.
It is an objective of this patent to provide along an outer edge or within the sign (when there is a surrounding border) raised surface signage having a Braille location indicator that is elevated or depressed below the level of the adjacent surface to provide a guide to locating the Braille characters which is not readily apparent to sighted persons.
The invention in its general form will first be described, and then its implementation in terms of specific embodiments will be detailed with reference to the drawings following hereafter. These embodiments are intended to demonstrate the principle of the invention, and the manner of its implementation. The invention in its broadest and more specific forms will then be further described, and defined, in each of the individual claims which conclude this Specification.
According to one aspect of the invention, in a raised surface sign with a Braille portion located on the surface of a rincipal layer of the sign, which principal layer also has a Braille position indicator or Braille locator positioned along its outside border in the form of a region that is elevated above or depressed below the surface area adjacent thereto, the visual presence of the Braille locator is masked by a coloured layer that spans the Braille locator and is of the same colour as adjacent areas of the principal layer.
According to a further aspect of the invention, a 3-D sign construction is provided which comprises:
(1) a sign face layer, wherein the sign face layer comprises a substantially transparent, conformable, thermoplastic shooting having an exposed face surface with Braille characters raised thereon;
(2) one or more visual characters underlying the sign face layer;
(3) one or more raised, 3-D characters in the form of a 3-D layer positioned beneath and in register with the visual characters;
(4) a principal background colour layer, underlying either the visual characters or both the visual characters and the 3-D characters and having an outer colour layer border; and
(5) a substrate layer underlying the principal background colour layer and having a substrate underside surface and a substrate border with a region that is elevated above or depressed below the adjacent surface area to form a Braille locator reference region, and that provides, at a location along its extent, a Braille locator that is a region within the sign that is elevated above or depressed below the adjacent surface area to such region,
wherein the Braille locator region is spanned by a coloured spanning surface that is part of the principal background colour layer or is of the same colour as the principal background colour layer to minimize visual contrast along the substrate border between the Braille locator region and the background colour layer. Preferably, the Braille locator is aligned with the Braille characters.
Adhesive layers, where required, may be interposed between the layers as listed above.
The coloured Braille locator region spanning surface may be provided by a portion of the principal background colour layer. Or, optionally, the sign construction of the invention may comprise, in the case of a recessed Braille locator, a secondary background layer that spans the locator region in the plane of said substrate underside surface. Such secondary background layer may be coloured over such region to provide said Braille locator region spanning surface. In either case, it is preferable for the sign face layer to span the reference region as well.
A principal distinction over the prior art is that a coloured surface spans the plane of the Braille locator region to minimize the contrast between the locator region and the principal background colour layer. This is true even when the sign includes an extended outer border that protrudes beyond the substrate border. Such extended border may be provided by a backing of a colour that differs from the colour of the principal background colour layer. When such backing is present the Braille locator region may be spanned by a coloured surface that does not contrast with the principal background layer.
The order of the layers may allow the principal background colour layer to either underlie both the visual characters and 3-D layer, or be positioned intermediate the visual characters and 3-D layer, as described in the prior art patents. The sign face surface may span not only the Braille locator region and the vertical sides of the Braille locator region and substrate boundary, but may also span the extended border, if present.
Preferably, the visual characters are cut from a cuttable material having a thickness in the range of 1-5 mils and the 3-D characters are cut from a cuttable material having a thickness in the range of 10-50 mils.
Preferably, the Braille characters raised from the face surface of the sign face layer, and optionally through the background colour layer, are filled with a filler, such as a chemically activated 2-part epoxy. This is to prevent the Braille from collapsing, and to deter vandalism.